What is a reason why caustic-soda softening is not popular?

What is a reason why caustic-soda softening is not popular?

• A. It requires specialized equipment.
• B. It increases total dissolved solids in water.
• C. It reduces water pH significantly.
• D. It is environmentally hazardous.

Answer: (B)

Caustic-soda softening involves the addition of sodium hydroxide (caustic soda) to hard water to precipitate calcium and magnesium ions, which are responsible for water hardness. One notable consequence of this process is that it increases the total dissolved solids (TDS) in the water. This occurs because the sodium ions from the caustic soda become part of the water's ionic composition, effectively contributing to the overall levels of dissolved substances present. An increase in TDS can be undesirable in many applications, particularly in industrial processes and drinking water supply systems where lower TDS levels are preferred for various reasons, including taste, corrosion potential, and overall water quality. As a result, the increase in TDS is a significant factor that limits the popularity of caustic-soda softening when considering options for water treatment.

Caustic-soda softening involves the addition of sodium hydroxide (caustic soda) to hard water to precipitate calcium and magnesium ions, which are responsible for water hardness. One notable consequence of this process is that it increases the total dissolved solids (TDS) in the water. This occurs because the sodium ions from the caustic soda become part of the water's ionic composition, effectively contributing to the overall levels of dissolved substances present.

An increase in TDS can be undesirable in many applications, particularly in industrial processes and drinking water supply systems where lower TDS levels are preferred for various reasons, including taste, corrosion potential, and overall water quality. As a result, the increase in TDS is a significant factor that limits the popularity of caustic-soda softening when considering options for water treatment.